The present invention relates to humectants or moisturizers for personal or animal care products which are encapsulated in lipid vesicles. Lipid vesicle encapsulation provides controlled delivery and permits use of incompatible ingredients. The humectant of the invention is particularly useful as a moisturizer for external use, e.g., as an additive in medicated shampoos.
Phospholipids are the basis of most lipid vesicles tried to date because of their chemical similarity to the materials forming natural membranes. However, the high cost of purified phospholipids has limited their usefulness to preparations which could justify the large expenditure. Humectants for external use, e.g., shampoos, cream rinses, skin creams, and other external human or animal use, do not have a sufficiently high cost to make encapsulation with phospholipids economically feasible.
Surfactants and other nonphospholipid vesicles make areas which heretofore fiscally infeasible now possible. For example, L'Oreal has a "niosome" line of products which is based on nonphospholipid materials, and the present inventor and others at Micro Vesicular Systems have developed techniques for formation and utilization of nonphospholipid materials which yield results that were considered impossible only a few years ago. These new techniques and materials make everyday use of lipid vesicles a reality.
Accordingly, an object of the invention is to provide lipid vesicles which can encapsulate moisturizing materials to act as humectants in animal care products.
Another object of the invention is to provide encapsulated moisturizers for personal care products.
A further object of the invention is to provide a humectant in medicated external preparations for human and animal use.
These and other objects and features of the invention will be apparent from the following description and the claims.